Each of the hotel's five main departments is managed by a director (e.g., director of hospitality).

The Front Desk subunit, which is supervised by the front desk manager, handles the hotel's reservations,

room assignments, guest payments, and key control. The Bell Staff, managed by the bell captain,

is responsible for greeting guests, front door service, assisting guests with their luggage, and delivering

room-service orders. The Guest Services subunit, supervised by the manager of Guest Services, is

responsible for assisting guests with local transportation arrangements, advising guests on tourist attractions,

and such conveniences as valet and floral services.

Subunits are: 1) the front desk, 2) bell staff, and 3) guest services

QUESTION:

I am looking for what each of these subunits are (e.g., cost center, revenue center, profit center, etc...) so I can develop a reasoning behind why they are such a center.